Nowadays, power socket outlets have slots or holes which accept the pins or blades of power plugs inserted into them and deliver electricity to the plugs. Sockets are usually designed to reject any plug which is not built to the same electrical standards, which typically vary in voltage and frequency. There are two main electrical standards, one the North American standard of an alternating current (AC) at 110-120 volts at 60 Hz and the other the European standard of AC at 220-240 volts at 50 Hz. Other countries have adopted one of these two voltage standards, although some countries use variations or a mixture of standards. Since sockets are usually designed to reject any plug which is not built to the same electrical standards, a transformer for adjusting the voltage to a required voltage, and a mechanical adaptor for connecting the socket to the plug of the electrical device, are required. Alternatively, different variations of products can be designed and manufactured, each variation being suited for specific voltage and frequency requirements.
To minimize the difficulty of designing for different national standards, many manufacturers of electrical devices, like personal computers, have adopted the practice of placing a single world-standard IEC (International Electrotechnical Commission) connector on the device, and supplying for each country a power cord equipped with a standard IEC connector on one end and a national power plug at the other. However, the IEC connector must be compatible in its design to fit the plug of the electrical device and the socket. The IEC connector must also be compatible with electrical standards of a designated country.
A surge protector and other types of high voltage protectors are designed to protect electrical devices from voltage spikes. Surge protectors attempt to regulate the voltage supplied to an electric device by either blocking or shorting to ground voltages above a safe threshold. Over time, surge protectors lose their ability to protect against power surges. Most surge protectors are an additional appliance connected between the socket and the electrical device. Therefore, they must be compatible with the socket jacks and the device plugs. There are three important features in a surge protector. First is the clamping voltage, which is the voltage level that will activate the oxide varistors (MOVs) to conduct electricity to the ground line. A lower clamping voltage indicates better protection. There are three levels of protection: 330 V, 400 V and 500 V. For most purposes, a clamping voltage more than 400 V is too high.
The second feature is the energy absorption/dissipation estimation, which is an estimation of how much energy the surge protector can absorb before it fails. A higher number indicates greater protection. A surge, protector should be rated between 200 to 400 joules at least, and at 600 joules or more for better protection. The third feature is the response time. The longer the response time, the longer the plugged electrical device will be exposed to the surge. Therefore, it is essential that the surge protector will respond quickly. In case there is no external high-voltage protector, the device is exposed to voltage spikes which may cause burning of an internal component in the device.
Other types of wall sockets include communication sockets, for transferring data over telephone lines and over data lines. As an example, in the communication networking field, a router is required to extract a destination of a data packet it receives, select the best path to that destination, and forward data packets to the next device along this path. Routers connect networks together, a LAN to a WAN for example, to access the Internet.
There is known from publication CN 2686148, a control panel for a plurality of sockets which includes a slot for a pre-paid card for controlled consumption of electricity. The card includes data indicating the amount of electricity for consumption that has been paid for in advance, like a pre-paid phone card. When the pre-paid card is inserted in the slot, the panel can read the information on the card which indicates the amount of consumption time which has been purchased and is still unused, and switches off the current when the pre-paid time has elapsed. This card does not affect the nature of the current, or the power that passes through the sockets.
Accordingly, there clearly remains a need for a versatile smart socket to which additional features can be added, such as a high-voltage protector or a transformer, which can be replaced or repaired easily and simply, and it would be desirable if the characteristics of the output of the socket could be selected and modified as desired.